1. Field Of The Invention
This invention relates to apparatus for clamping tire tubes for facilitating repair thereof, and more particularly, to a tire tube clamping apparatus having yoke-mounted clamping bars for clampingly engaging a tire tube positioned on a mandrel.
2. Description Of The Prior Art
One previous device for holding inner tubes is disclosed in U.S. Pat. No. 2,384,803 to Anderson which includes a fixed mandrel and clamping arms which are normally raised above the mandrel. Pressing on a foot lever brings the arms down to engage and clamp a tire inner tube positioned on the mandrel. A latch may be used to hold the foot pedal in the clamping position. This device has the disadvantage of requiring the operator to physically hold the foot pedal down or to engage a latch. In the present invention, clamping bars are normally biased toward the mandrel and are raised therefrom only by actuating a foot pedal.
In another device of Anderson, disclosed in U.S. Pat. No. 2,509,328, fingers on a pair of arms are again used to clamp a tire tube to a mandrel. In operation, the operator presses the mandrel downwardly to overcome the tension provided by springs and must move the mandrel laterally away from, or toward, the fingers. Once aligned with the fingers, the downward pressure on the mandrel is relieved and the spring biases the mandrel upwardly toward the fingers, clamping the tube. This device has the disadvantage of requiring all movement to be carried out by the hands of the operator, and thus positioning of the tube on the mandrel during the clamping operation is difficult. The present invention and the earlier Anderson patent utilize foot actuation.
Previous devices which show pivoted clamping members include Harris U.S. Pat. No. 3,088,348;Brotherman U.S. Pat. No. 1,867,248 et al.; and Parvin U.S. Pat. No. 1,729,121.
The present invention also utilizes clamping bars mounted on a substantially U-shaped yoke which allows flexibility when clamping a tire tube on the mandrel. The present invention further has a mandrel spaced from the yoke and mounted on a vertical member which does not interfere in any way with the positioning of the tire tube on the mandrel, unlike devices in the prior art.